• Title/Summary/Keyword: A516-60

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A Study on the Safe Blasting Design by Statistical Analysis of Ground Vibration for Vibration Controlled Blasting in Urban Area (II) (도심지 미진동 제어발파에서 진동분석을 통한 안전 발파설계에 관한 연구(II) - 진동측정 자료의 통계적 분석을 위주로 -)

  • 김영환;안명석;박종남;강대우;이창우
    • Explosives and Blasting
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    • v.18 no.2
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    • pp.7-13
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    • 2000
  • Abstract The characteristics of bed rock in the study area was classified by means of the crack coefficient estimated from the seismic velocities of in-situ and intact rocks. Various statistical methods were investigated in order to minimize the possible errors in estimating the predictive equation of blasting vibration and to enhance the determination coefficient $R^2$, for more reliable estimation. The determination coefficient showed the highest in the analysis for those groups using weighting function with the number of samples. The analysis for the weighting function employed with standard coefficient and variance also enhanced the determination coefficients significantly compared to the others, but the reliability was slightly lower than results obtained former method. Therefore the most reliable predictive equation of blasting vibration was found to be obtained from a regression analysis of the mean vibration level using the weighting of same distance groups within 15m with the same explosive charge weight per delay. The coefficients, K and n 317.4 and -1.66, respectively, when using the square root scaling, and 209.9 and -1.66, respectively, when using the cube root scaling. The analysis also showed that the square root scaling may be used in the distance less than 31m form the blast source, and the cube root scaling in the distance more than 31m for safe design.

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Studies in the Consumption and Preference for Sprout Vegetables (새싹채소의 기호도 및 이용 실태)

  • Lee, Kyung Sook;Park, Geum Soon
    • Journal of the East Asian Society of Dietary Life
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    • v.24 no.6
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    • pp.896-905
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    • 2014
  • The purpose of this study was to investigate the use and perception of adults concerning sprout vegetables. Self-administered questionnaires were collected from 516 residents in the Daegu and Gyeonbuk areas. When purchasing sprout vegetables, respondents answered that they considered freshness, eco green, and price. Consumers purchased sprout vegetables to make bibimbap (58.9%) and salad (29.3%). Approximately 81.4% of respondents answered that they purchased sprout vegetables in grocery and department stores. Once or twice per month was the highest purchase frequency for sprout vegetables. Regarding knowledge of sprout vegetables, radish sprout score was the highest (3.14), whereas preference was highest for barley grass (3.00). When asked how much they like sprout vegetable menus, subjects responded that they liked bibimbap (3.79), salad (3.73) and bibim noodles (3.58). As a result, popularization of sprout vegetables was based on product quality factor and sales promotion factor significantly influenced preference for sprout vegetable menus. To increase consumption of sprout vegetables, there is a need for hygiene and safety of sprout products and variations and improvement of quality.

Quality Characteristics of Bread Added with Black Sesame Powder (흑임자를 첨가한 식빵의 품질특성)

  • Choi, Soon-Nam;Chung, Nam-Yong
    • Korean journal of food and cookery science
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    • v.21 no.5
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    • pp.655-661
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    • 2005
  • This study was carried out to evaluate the effects of black sesame powder on bread quality. Breads were prepared by the addition of 0, 2.5, 5.0 and 7.5% of black sesame powder to the basic formulation. The weight of bread with black sesame powder ranged from 522.0 to 532.0 g and that of the control was 516.0 g. The volume of the bread prepared by adding 2.5, 5.0 and 7.5% black sesame powder was 2250.0, 2290.0, and 1800.0 mL, respectively. The water absorptive rate of bread with added black sesame powder decreased 3.83 to 2.48 and that of the control was 5.28. The lightness, redness and yellowness values of the bread decreased with the increase of black sesame powder. The hardness increased with the addition of black sesame powder, and was the highest for the bread with added 7.5 % black sesame powder. The sensory quality of the black sesame powder-bread as estimated by taste, and overall acceptability was better than that of the control product, and especially the quality of the bread with the addition of 2.5% black sesame powder was the best.

Salt Tolerance and Green Fodder and Grain yields of Barnyard Millet(Echinochloa crusgalli var. frumentacea) (재배 피 품종의 내염성과 청예 및 종실 수량성)

  • Keun-Yong Park;Rae-Kyung Park;Byeong-Han Choi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.3
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    • pp.249-253
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    • 1991
  • Barnyard millet (Echinochloa crusgalli var. frumentacea) has been detected as the best fodder crop in Korea for earlier and/or later season crop. The objective of the study was to examine varieal differences among the varieties introduced from ICRISAT and cultivated in Korea for salt tolerance and green fodder and grain yield under the saline and normal upland soil conditions, IEC 514, IEC 515, IEC 518 and IEC 528 introduced from ICRISAT were relatively highly tolerant to saline soil and with higher green fodder and grain yields, and also were very earlier headed and matured as compared with the Korean local varieties and King.

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Prevalence of Opisthorchis viverrini Infection in Nakhon Ratchasima Province, Northeast Thailand

  • Kaewpitoon, Soraya J.;Rujirakul, Ratana;Kaewpitoon, Natthawut
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.5245-5249
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    • 2012
  • Background: Opisthorchis viverrini infection is a serious public-health problem in Southeast Asia especially in Lao PDR and Thailand. It is associated with a number of hepatobiliary diseases and the evidence strongly indicates that liver fluke infection is the major etiology of cholangiocarcinoma. Objectives: This study aimed to determine actual levels of Opisthorchis viverrini infection in Nakhon Ratchasima province, Northeast Thailand. Methods: A cross-sectional survey was conducted during a one year period from October 2010 to September 2011. O. viverrini infection was determined using a modified Kato's thick smear technique and socio-demographic data were collected using predesigned semi-structured questionnaires. Results: A total of 1,168 stool samples were obtained from 516 males and 652 females, aged 5-90 years. Stool examination showed that 2.48% were infected with O. viverrini. Males were slightly more likely to be infected than females, but the different was not statistically significant. O. viverrini infection was most frequent in the 51-60 year age group and was found to be positively associated with education and occupation. Positive results were evident in 16 of 32 districts, the highest prevalence being found in Non Daeng with 16.7%, followed by Pra Thai with 11.1%, Kaeng Sanam Nang with 8.33%, and Lam Ta Men Chai (8.33%) districts. Conclusion: This study indicates that O viverrini is still a problem in some areas of Nakhon Ratchasima, the patients in this study bing suitable for the purpose of monitoring projects.

Effect of black sand as a partial replacement for fine aggregate on properties as a novel radiation shielding of high-performance heavyweight concrete

  • Ashraf M. Heniegal;Mohamed Amin;S.H. Nagib;Hassan Youssef;Ibrahim Saad Agwa
    • Structural Engineering and Mechanics
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    • v.87 no.5
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    • pp.499-516
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    • 2023
  • To defend against harmful gamma radiation, new types of materials for use in the construction of heavyweight concrete (HWC) are still needed to be developed. This research introduces new materials to be employed as a partial replacement for fine aggregate (FA) to manufacture high-performance heavyweight concrete (HPHWC). These materials include hematite, black sand, ilmenite, and magnetite, with substitution ratios of 50% and 100% of FA. In this research, the hardening and fresh characteristics of HPHWC were obtained. Concrete samples' Gamma-ray linear attenuation coefficient was evaluated utilizing a gamma source of Co-60 through the thicknesses of 2.5, 5, 7.5, 10, 12.5, and 15 cm. High temperatures were studied for HPHWC samples, which were exposed to up to 700℃ for two hours. Energy-dispersive x-rays and a scanning electron microscope carried out microstructure analyses. Magnetite as an FA attained the lowest compressive strength of 87.1 MPa, but the best radiation protection characteristics and the highest density of 3100 kg/m3 were achieved. After 28 days, the attenuation efficiency of concrete mixtures was increased by 6.5% when fine sand was replaced with black sand at a ratio of 50%. HPHWC, which contains hematite, black sand, ilmenite, and magnetite, is designed to reduce environmental and health dangers and be used in medicinal, military, and civil applications.

Effective removal of non-radioactive and radioactive cesium from wastewater generated by washing treatment of contaminated steel ash

  • P. Sopapan;U. Lamdab;T. Akharawutchayanon;S. Issarapanacheewin;K. Yubonmhat;W. Silpradit;W. Katekaew;N. Prasertchiewchan
    • Nuclear Engineering and Technology
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    • v.55 no.2
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    • pp.516-522
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    • 2023
  • The co-precipitation process plays a key role in the decontamination of radionuclides from low and intermediate levels of liquid waste. For that reason, the removal of Cs ions from waste solution by the co-precipitation method was carried out. A simulated liquid waste (133Cs) was prepared from a 0.1 M CsCl solution, while wastewater generated by washing steel ash served as a representative of radioactive cesium solution (137Cs). By co-precipitation, potassium ferrocyanide was applied for the adsorption of Cs ions, while nickel nitrate and iron sulfate were selected for supporting the precipitation. The amount of residual Cs ions in the CsCl solution after precipitation and filtration was determined by ICP-OES, while the radioactivity of 137Cs was measured using a gamma-ray spectrometer. After cesium removal, the amount of cesium appearing in both XRD and SEM-EDS was analyzed. The removal efficiency of 133Cs was 60.21% and 51.86% for nickel nitrate and iron sulfate, respectively. For the ash-washing solution, the removal efficiency of 137Cs was revealed to be more than 99.91% by both chemical agents. This implied that the co-precipitation process is an excellent strategy for the effective removal of radioactive cesium in waste solution treatment.

Impact of Diabetes Duration on the Cardiovascular Disease Risk Factors in Korea Type 2 DM Patients (제 2형 당뇨병 환자의 이환기간에 따른 심혈관계 질환 위험요인 분석)

  • Hong, Hye-Sook;Ryu, Han-Kyoung;Park, Jong-Suk;Kim, Wha-Young
    • Journal of Nutrition and Health
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    • v.40 no.6
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    • pp.509-516
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    • 2007
  • The purpose of this study was to investigate the impact DM duration on cardiovascular disease risk factors in Korean Type 2 diabetes mellitus patients. The subject were 250 (male: 134, female: 118) Korean Type 2 DM patients recruited from a general hospital's DM clinic. Anthropometric and hematological variables and dietary intake were assessed. The subject's mean age was 60.2 years and duration of diabetes was 9.5 years. As far as DM duration was concerned, male subjects with long duration (${\geq}$ 5 years and longer) showed significantly lower weight, fat free mass, skeletal muscle mass, BMI (p < 0.05) and higher 2hrs-postprandial plasma glucose (p < 0.05) and concentration of Hemoglobin A1c (p < 0.01) compared to those with less 5years of duration. In female subjects, same trend was found. Female subjects with long duration (${\geq}$ 5 years and longer) showed significantly higher fat free mass (p < 0.05) and skeletal muscle mass (p < 0.05), Hemoglobin A1c (p < 0.01), HDL-cholesterol (p < 0.01) and triglyceride (p < 0.05), dietary intakes of protein (p < 0.05) and fat (p < 0.05) compared to those with less 5years of duration. In conclusion, Type II DM patients of long duration had higher blood lipid concentrations and higher carbohydrates intakes. Subjects followed diet prescription strictly showed lower blood lipid concentration, suggesting the effectiveness of diet to manage Type 2 DM patients.

Effect of Reverse Cyclic Loading on the Fracture Resistance Curve of Nuclear Piping Material (역사이클하중이 원자력 배관재료의 파괴저항곡선에 미치는 영향)

  • Weon, Jong-Il;Seok, Chang-Sung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.23 no.7 s.166
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    • pp.1112-1119
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    • 1999
  • Fracture resistance(J-R) curves, which are used for the elastic-plastic fracture mechanics analyses, are known to be dependent on the cyclic loading history. The objective of this paper is to study the effect of reverse cyclic loading on J-R curves in CT specimens. The effect of two parameters was observed on the J-R curves during the reverse cyclic loading. One was the minimum-to-maximum load ratio(R) and the other was the incremental plastic displacement(${\delta}_{cycle}/{\delta}_i$), which is related to the amount of crack growth that occurs in a cycle. Fracture resistance test on CT specimens with varying load ratio and incremental plastic displacement were performed. For the SA 516 Gr. 70 steel, the results showed that the J-R curves were decreased with decreasing the load ratio and the incremental plastic displacement. When the load ratio was set to -1, the results of the J-R curves and the $J_i$ value were about $40{\sim}50$ percent of those for the monotonic loading condition. Also on condition that the incremental plastic displacement reached 1/40, the J-R curves and the $J_i$ value were about $50{\sim}60$ percent of those for the incremental plastic displacement of 1/10.

Solublity Patterns and Gelatinization Properties of Waxy Rice Starches (가열에 따른 찹쌀전분 호화액의 특성)

  • Song, Ji-Young;Shin, Mal-Shick
    • Applied Biological Chemistry
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    • v.41 no.7
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    • pp.516-521
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    • 1998
  • Solubility patterns and gelatinization properties of two waxy rice starches, Sinsunchalbyeo and Hwasunchalbyeo, were investigated. Shapes of all starch granules were round and polygonal, and their X-ray diffraction patterns were all A type. Amylose content and water binding capacity of Sinsunchalbyeo were similar to those of Hwasunchalbyeo. The swelling powers and solubilities of two starches were increased with increasing temperature in range of $65{\sim}95^{\circ}C$, and those of Hwasunchalbyeo was higher. Iodine affinities of soluble fractions in Sinsunchalbyeo starch were higher than those in Hwasunchalbyeo at the same temperature and both were increased with increasing temperature. λmax of soluble fraction of Sinsunchalbyeo starch was highest at $75^{\circ}C$ of heating temperature. The transmittance of starch suspensions were increased rapidly at $60{\sim}65^{\circ}C$. By Rapid Visco Analyzer, initial gelatinization temperature of Sinsunchalbyeo was $67.2^{\circ}C$, and that of Hwasunchalbyeo was $68.2^{\circ}C$. In DSC analysis, onset temperature for gelatinization of Sinsunchalbyeo and Hwasunchalbyeo were $61.3^{\circ}C\;and\;62.9^{\circ}C$, respectively.

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